The present invention relates to a solenoid controlled valve for liquid preparation in which an electromagnetic force drives the plunger to release the valve body from the valve seat, causing the valve to be opened or closed, thereby to control the flow of a liquid.
In a conventional solenoid controlled valve for liquid preparation, an electromagnetic drive unit including a plunger to be driven by an electromagnetic force generated by the coil, is disposed in the vicinity of a valve unit including a valve body pressingly contacted with the valve seat by a spring. The plunger of the electromagnetic drive unit is connected to the valve body of the valve unit by a valve rod having rigidity.
When using solenoid controlled valves for liquid preparation, it is required to gather, at one place, the tips of the pipes for supplying liquids used for preparation. Accordingly, the pipes have been conventionally extended to a long distance from the valve units of the solenoid controlled valves. When the pipes are extended to a long distance from the valve units, the liquids may remain in and stick to the insides of the pipes, thus failing to achieve an accurate preparation.
Further, when the valve unit is disposed in the vicinity of the electromagnetic drive unit, the heat of the coil is transferred to the valve body through the valve rod. Accordingly, some liquids to be controlled may be dried and solidified, due to this heat, between the valve seat and the valve body. This causes the liquid concentration to vary, failing to assure an accurate preparation.
In view of the foregoing, it is an object of the present invention to provide a solenoid controlled valve for liquid preparation in which the liquid does not remain in the liquid supply pipe and is not dried and solidifed at the valve unit, thus assuring an accurate liquid preparation.